Light-diffusing unit



June-17, 1958 I J, cu 2,839,671

LIGHT-DIFFUSING UNIT Filed Jan. 15. 1956 IN V EN TOR.

LIGHT-DIFFUSING UNIT James L. Cullen, Glendale, Calif., assignor to Harry H. Shearin, SanMarino, Calif.

Application January 13,1956, Serial No. 558,954

13 Claims. (Cl. 240-9) This invention relates to a light-diffusing unit and more particularly to a modular light-diffusing ceiling unit providing high and efficient illumination with low brightness or glare.

The invention contemplates a modular luminous ceiling unit constructed and arranged to be readily assembled with like units to occupy a selected ceiling area or to be employed in a light fixture of-any selected shape or form. The joint lines of such assembled units are substantially unnoticeable so that a uniform overall appearance is provided without distracting longitudinal or transverse lines of juncture. Area to be occupied by luminous units of this invention need not be of any preselected dimension or size because symmetry of appearance of assembled units is maintained.

Prior proposed ceiling units or fixtures have usually included polygonal shapes such as square andhexagonal. In the assembly of such prior proposed units longitudinal and lateral joint lines were quite noticeable. Such prior proposed units were generally difiicult to fabricate, required considerable labor and time, and as a result were costly to manufacture. Other disadvantages included the difficulty of installing or hanging such units and as a rev sult their application to certain installations was quite limited. v

This invention contemplates a novel construction and arrangement of a light-diffusing unit of translucent moldable material.

An object of the invention is to disclose and provide that a desired light cut-elf angle may be readily provided and selectively varied to provide a virtually luminous ceiling unit.

A further object of this invention is to disclose and provide a light-diffusing unit which may be conveniently and readily assembled with like units so as to eliminate from the appearance of assembled units unattractive undesirable joint lines.

A still further object of the invention is to disclose and provide a molded light-diffusing unit made of transv lucent polymerizable material wherein a plurality of f'cylindrical elements are arranged in spaced relation with curvilinear surfaces thereof merging with planar surfaces provided on thin web elements which interconnect and support said cylindrical elements.

. .A still further object of this invention is to disclose and provide a light-difiusing unit which includes a plurality of spaced cylindrical elements of thin wall section integrally interconnected with thin web elements, said cylindrical elements and web elements lying perpendicular to top and bottom faces of the unit, which faces lie in parallel planes.

The invention contemplates an assembly of such lightdifiusing units as described above wherein edges of said United States Patent O units are complementary in form and wherein extensions are provided on certain of said elements to provide a convenient concealed means for inter-connecting said units.

The invention also contemplates such a light-diffusing unit wherein the web elements interconnecting the cylindrical elements are provided with bottom edges spaced from the bottom face of the unit so as to be substantially unnoticeable.

It will be readily understood by those skilled in this art that various other objects and advantages will be apparent from the following descriptionof the drawings in which an exemplary embodiment of this invention is shown.

In the drawings:

Fig.1 is a fragmentary side elevational view showing assembled light-diffusing units of this invention;

Fig. 2 is a top plan view of a portion of Fig. 1;

Fig. 3 is a sectional view taken in the plane indicated by line lll1ll of Fig. 2; and

Fig. 4 is a sectional view taken in the plane indicated by line IVIV of Fig. 2. f

In Fig. 1 a plurality of assembled light-diffusing units 10 embodying this invention are illustrated as being located below a ceiling surface 11 and below a suitable light source 12. The unit 10 may be supported from the ceiling as by hanger means generally indicated at 13 and which will be described hereinafter. The modular lightdiifusing units 10 may be assembled to conform to any size or area of a room and if desired units 10 mayextend from wall to wall to provide a false or dropped ceiling of luminous characteristics. Such a luminous ceiling will appear to be virutally continuous and uniform in appearance both laterally and longitudinally. It will also be apparent that the ceiling units may be assembled in different manner so as to provide selected light patterns and if desirable may be mounted in well known standard lighting fixtures.

Each unit It may be fabricated as by molding of a suitable polymerizable plastic composition material. The composition material selected is preferably translucent although it may include material having fluorescent or opalescent charactertistics. In some instances it may be desirable to employ opaque material provided with The thin-walled sections of the cylindrical elements 17 surfaces.

may include a virtually unnoticeable taper in thickness in order to permit said units to be easily withdrawn from their molds at the conclusion of a molding process.

It is understood that the term cylindrical element includes any elongated body having external curvilinear It is understood that any element whichineludes curvilinear surfaces which are continuous and the unit, such as 60 in the present example.

which may merge smoothly with other surfaces are included within the meaning of cylindrical elements.

The cylindrical elements 17 may be arranged in parallel rows disposed at a selected angle to an edge of It is understood that the cylindrical elements may be arranged in rows disposed at or some other suitable selected angle with respect to an edge of the unit.

The cylindrical elements 17 are disposed 1n spaced relationto each other, each being spaced an equal distance -17' in a unitare the same. that the outer diameter of a cylindrical element 17 does not'appreciably exceed the distance separating the spaced top and bottom faces 15, 16.

, adjacent 'unim in assembly.

includes a distance which should not be less than oneeighth nor. more than one-half the outer diameter of a cylindrical element. The selected spacing is uniform throughout a unit and it may be noted at this time that the outer and inner diameters of cylindrical elements It is also important to note integrally formed with and interconnecting said cylindrical elements 17 may be a plurality of thin section web elements 18 lying in planes perpendicular to the top and bottom faces 15 and 16. The top edges 19 'of said web elements may lie in the plane defined by the top face of the unit. Bottom edges 24) of said web elements may lie in a plane parallel to the top and bottom faces and intermediate said faces, said bottom edges 20 being spaced above bottom face 16 of a unit a suflicient distance so as to normally be non-observable when the bottom face of a unit is viewed from an angle. The Web elements 18 may'interconnect the cylindrical elements 17 along longitudinal and diagonally disposed lines diametrical to the cylindrical elements.

It will be noted that the described arrangement of cylindrical elements 17 and webs 18 of selected spacing,

' diameter, and distance between top and bottom faces provides a light-diffusing unit having a cut-off angle for light emanating from said light source of approximately 45, said light cut-off angle of 45 being recognized as desirable in the field of illumination engineering so as to prevent light rays from a light source from directly impinging upon the eyes of a person normally observing 21 is joined to a corresponding opposite edgeface 21 I of an adjacent unit the complementary half cylindrical elements and edge web elements 18 will form a continuous uninterrupted pattern without making a noticeable joint line. In this respect it should be remembered that web elements 18 are spaced well above the bottom face of the unit and are normally unnoticeable.

The other pair of opposite edge faces 21a on each unit may comprise a plurality of half cylindrical elements unconnected along the edge of said face except at each corner where a web element 22 may extend between a corner quarter cylindrical element 23 and a half web element 18 extending from an adjacent cylindrical element 17. The web element 22 affords additional support for the quarter cylindrical element 23 and provides a guide face for positioning a corresponding edge face 21a provided onan adjacent unit 10. The edges of the half cylindrical elements 17 and half web elements '18 may be brought into alignment so that this line of juncture is substantially unnoticeable.

Means to interconnect adjacent units may comprise an upwardly directed cylindrical extension 25 provided on certain of said cylindrical elements disposed along peripheral margins of said unit. In this example a cylindrical extension is provided at the quarter section 23 and extends above the top face of the unit. When adjacent units are assembled a resilient, elastic,

narrow, preformed sleeve ring 26 of selected inner diameter may be urged over the cylindrical extensions 25 so as toghold. adjacent abutting extensions 25 of It will be remembered that a slight taper is provided onsaid cylindrical elements 4 l to facilitate molding and this slight taper serves to provide a wedge face cooperable with the sleeve ring 26 to tightly bring the cylindrical extensions together in proper assembled relation. In addition to the top securing ring 26, a similar bottom securing ring 27 may be applied to lower portions of the joined abutting quarter cylindrical elements. It should be noted that bottom securing ring 27 lies substantially above the bottom face 16 of the unit and therefore is virtually unnoticeable.

Although cylindrical extensions 25 are shown at the quarter cylinderelement 23, it is understood that such extensions may be provided on other cylindrical elements located at or adjacent margins of the unit. Cylindrical extension 25 on elements 17 next to corner quarter elements 23 on one or more units 10 may be desirable to facilitate construction and hinging of an assembly of units forming a door in the false ceiling for access to the space thereabove.

Means 13 to suspend a plurality of said units from a ceiling in a horizontal planar zone may comprise an engagement means provided at the top of certain web elements, each engagement means being in the form of horizontal oppositely extending flanges 29 each integral with a selected Web element 18. Preferably the flanged Web elements 18 are provided adjacent'each quarter cylinder element 23. In section the flanges 29 may form a T with the abutting web elements 18 as shown in Fig. 3. Flanges 29 are engaged by inwardly biased recessed end portions 3t provided on opposed ends of a bifurcated grappling type hook or hanger 31. The hanger 31 may be made of thin spring metal having a central ported section 31a from which depend two spaced pairs of hanger legs 31b, said central section 31a straddling assembled corner elements 23 so that only one hangeris employed to join said units at a common corner. The legs 31b of each pair are biased toward each other with extremities of said legs being flared outwardly so that assembled units 10 may be pressed upwardly and flanges 29 snapped into opposed recessed portions 31} for grasping reception thereof. Each hanger: 31 may be carried in any suitable manner by a hanger bolt 32 fixed to the ceiling, extending through the ported section 31a and having a threaded lower end portion provided with an adjustment nut 33 whereby said hanger 31 may be readily vertically adjusted.

' diffusing units 10 of this invention. Such light beams are reflected from planar surfaces of thin web elements 18 and are reflected and ditfused in different directions by the external curvilinear surfaces provided on cylindrical elements 17. Since unit 10 is made of a translucent material some of the light beams are also transmitted through the cylindrical elements and webs. Light transmitted by cylindrical elements is further diffused in the hollow form of the cylindrical element. Light reflected from external surfaces of the cylindrical elements is also reflected downwardly and angularly against lower portions of adjacent cylindrical elements. It will thus be apparent to those skilled in the art that beams of light from the light source are virtually uniformly diffused by the reflection and transmission characteristics of the interconnected spaced cylindrical element construction of light-difiusing units 10. A high percentage of light is transmitted and diffused by units 10 so as to provide highly efiicient illumination of areas beneath said unit. The .difrusing characteristics of unit 10 is such that while high illumination is provided thereby, low brightness or glare is also afforded thereby. Since the material of thelightdiffusing unit is translucent, fluorescent or opalescent, it will be readily apparent that a luminousv ceiling unit is providedlf'afterglow effects are desired after the-light source has been turned out, the units may be coated with a phosphorescent material. 7 v

If desired, the edges of the cylindrical elements and webelements at the ,top. and bottom'faces of the unit maybe etched in well known manner. Etching of said edges produces a light efiect wherein light is conducted along and through the walls of the 'cylindrical'elements and web' elements. Such edge-lighting produces an unusual lighting effect in combination with the reflection and difiusion of light beams produced by external and internal surfaces of the cylindrical elements and the surfaces of the-thin web elements. I I

It will thus be readily understood by those skilled in this art that a novel light-diffusing unit has been provided which is inexpensive to manufacture because of its readily moldable construction and which produces an unusual luminous ceiling arrangement. It will be clear from the description above that installation of a plurality of such light-diffusing units 10 in a horizontal or planar zone will create an appearance of a continuous integral luminous ceiling assembly. Unattractive undesirable joint lines extending laterally or longitudinally will not be apparent to an observer. The particular arrangement of cylindrical elements in spaced relation permits the use of these units over areas of any configuration and size without creating an unsymmetrical appearance. understood that the cylindrical elements may be of selected size, proportioned as above described and a unit 10 may include cylindrical elements of difierent inner diameter to create unusual aesthetic eifects.

It will be understood by those skilled in the art that various modifications and changes may be made inthe spacing, size and interconnection of the cylindrical elements described above and any such modifications coming within the'scope of the appended claims are embraced thereby.

-Iclaim:" f I 1. A light-diffusing modular unit for ceilings and the like adapted to provide high and eflicient illumination and .low brightness, comprisingLa one-piece unit having substantially planar and'parallel spaced 'top and bottom faces molded from a fluorescent polymerizable composition; each unit comprising a plurality of thin-walled, cy-

lindrical elements with axes perpendicular to said faces,

said cylindrical elements being arranged in rows at 60 to each other, the diameter of said cylindrical elements not appreciably exceeding the distance separating said spaced top and bottom faces, said cylindrical elements in each row being spaced from each other a distance not less than one-eighth the outer diameter nor more than one-half the outer diameter of each cylindrical element; thin web elements integral with said cylindrical elements extending therebetween to connect the same, said web elements lying in planes perpendicular to said faces whereby light from a source located to one side of said unit is diffused by the outer surface of said cylindrical elements and distributed by the surfaces of said web elements, peripheral edges of said unit being defined by parts of said cylindrical elementsand webs, flange means carried by certainof said Web elements adjacent the peripheral edge adapted'to be engaged with suspending units; certain of said part cylindrical elements having extensions extending beyond the plane of a face, and means engaging juxtaposed cylindrical extensions for connecting adjacent units.

2. A light-diffusing modular unit for ceilings and the like adapted to provide high and efficient illumination and low brightness, comprising: a one-piece unit having substantially planar and parallel spaced top and bottom faces molded from an opalescent polymerizable composition; each unit comprising a plurality of thin-walled, cylindrical elements with axes perpendicular to said faces, said cylindrical elements being arranged in rows, the diameter of said cylindricalelements not appreciably exceeding the distance separating said spaced top and It is.

spaced from each other; thin web elements integral with said cylindrical elements extending therebetween to connect the same, said web elements lying in planes perpendicular to said faces whereby light from a source located to one side of said unit is diifused by the outer surface of said cylindrical elements and distributed by the surfaces of said Web elements, flange means carried by certain of said web elements to be engaged with suspending units; certain of said cylindrical elements adjacent the peripheral edge of the unit extending beyond the plane of a face, and means securing together said cylindrical extensions for connecting adjacent units.

*3. A light-diffusing modular unit for ceilings and the like adapted to provide high and eflicient illumination and low brightness, comprising: a one-piece unit having substantially planar and parallel spaced top and bottom faces molded from an opalescent polymerizable composition; each unit comprising a plurality of thin-Walled,

cylindrical elements with axes perpendicular tosaid faces,

said cylindrical elements being arranged in rows, the diameter of said cylindrical elements not appreciably exceeding the distance separating said spaced top and bottom faces, said cylindrical elements in each row being spaced from each other; thin web elements integral with said cylindrical elements and extending therebetween to connect the same, said web elements extending from the top face of the unit, terminating in spaced relation to the bottom face, and lying in planes perpendicular to said faces whereby light from a source located to one side of said unit is diffused by the outer surface of said cylindrical elements and distributed by the surfaces of said web elements, support means carried by certain of said web elements.

4. A light-ditfusing modular unit for ceilings and the like adapted to provide high and eificient illumination and low brightness, comprising: a one-piece unit having spaced top and bottom faces molded from a translucent polymerizable composition; each unit comprising a plurality of thin-walled, cylindrical elements with axes perpendicular to said faces, said cylindrical elements being arranged in rows, said cylindrical elements in each row being spaced from each other a distance not less than one-eighth the outer diameter nor more than one-half the outer diameter of each cylindrical element; thin web elements integral with said cylindrical elements and extending therebetween to connect the same in spaced relation to the bottom face whereby light from a source located to one side of said unit is difiused by the outer surface of said cylindrical elements and distributed by the surfaces of said web elements, support means carried by certain of said web elements.

5. A light-diffusing modular unit for ceilings and the like adapted to provide high and elficient illumination and low brightness, comprising: a one-piece unit having spaced top and bottom faces molded from a translucent polymerizable composition; each unit comprising a plurality of thin-walled, cylindrical elements with axes perpendicular to said faces, said cylindrical elements being arranged in rows, said cylindrical elements in each row being spaced from each other; thin web elements integral with said cylindrical elements extending therebetween to connect the same, said web elements lying in planes perpendicular to said faces and extending from said top face into spaced relation to said bottom face whereby light from a source located to one side of said unit is diflused by the outer surface of said cylindrical elements and distributed by the surfaces of said web elements.

6. A light-diffusing modular unit for ceilings and the like adapted to provide high and eflicient illumination and low brightness, comprising: a one-piece unit having spaced top and "bottom faces molded from a translucent polymerizable composition; each unit comprising a plurality of thin-walled, cylindrical elements with axes perpendicular to said faces, said cylindrical elements being arranged in rows, said cylindrical elements in each row being spaced from each other; thin web elements integral with said cylindrical elements extending therebetween to connect the same, said web elements lying in planes perpendicular to said faces whereby light from a source located to one side of said unit is dilfused by the outer surface of said cylindrical elements and distributed by the surfaces of said Web elements, certain of said cylindrical elements adjacent the peripheral edge of the unit extending beyond the plane of the top face, and means engaging juxtaposed extensions for connecting adjacent units.

7. A light-diflusing unit for ceilings and the like, comprising: an integral unit of translucent material having parallel spaced top and bottom faces, each unit comprising a plurality of thin-walled, curvilinear elements having light-difiiusing surfaces disposed perpendicular to said top and bottom faces, said curvilinear elements being arranged in rows in spaced relation; thin web .elements interconnecting said curvilinear elements and having light-distributing surfaces lying perpendicular to said top and bottom faces and spaced above the bottom face whereby light from a source spaced from .said top face is diffused by said curvilinear surfaces and distributed by said distributing faces.

8. A unit as claimed in claim 7 wherein the spacing of diametrically opposite points on the light-diffusing surface of each curvilinear element does not appreciably exceed the distance separating said top and bottom faces.

9. A unit as claimed in claim 7 wherein said curvilinear elements are cylindrical and are spaced apart a distance not less than one-eighth the outer diameter nor more than one-half the outer diameter of each cylindrical element.

10. A unit as claimed in claim 7 wherein certain of said thin-walled elements are provided with extensions extending beyond the plane of the top face; and means embracing said extensions to interconnect adjacentnnits.

11. A unit as claimed in claim 7 wherein the zcurvilinear elements disposed along the periphery of said unit are complemental to such peripheral elements 'on .an adjacent unit whereby adjacent units may be formed with unnoticeable joint lines.

12. A light-diffusing fixture for ceilings and the like to provide high illumination and low. brightness, com

prising: a plurality of integral units of translucent material having spaced top and bottom faces, each unit comprising a pluralityof cylindrical elements in spaced relation in rows and interconnected by webelements, said cylindrical and web elements lying in perpendicular relation to said top and bottom faces; cylindrical and web elements at the peripheral edges of each unit opposed to the edge of an adjacent unit being complementary in form; certain of said elements having extensions projecting beyond said top face; and means interconnecting said extensions of adjacent units.

13. A light-diffusing fixture for ceilings and the like V to provide high illumination, low brightness, and uniform joint-free appearance, comprising: a plurality of integral units of light-transmitting material, each unit comprising a plurality of discrete curvilinear elements in spaced relation in rows and defining top and bottom faces of said unit, web elements interconnecting said curvilinear elements and having bottom web edges spaced above the bottom face of the unit, each unit having peripheral edge faces including portions of said curvilinear elements adapted to match corresponding portions of adjacent units whereby joint lines between adjacent units are unnoticeable, and means adjacent the top faces of said units for interconnecting adjacent units.

References Cited in the file of this patent UNITED STATES PATENTS 1,136,006 Harrison Apr. 20, 1915 1,659,409 Porter Feb. 14, 1928 1,765,652 Burgess June 24, 1930 1,962,648 Pflueger June 12, 1934 2,299,256 Schultz Oct. 20, 1942 2,659,808 Beckwith Nov. 17, 1953 2,677,046 Dunne Apr. 27, 1954 FOREIGN PATENTS 699,993 Great Britain Apr. 9, 1952 

